This is a proposal to study the biochemistry of adenosine 3',5'-monophosphate (cyclic AMP) and guanosine 3',5'-monophosphate (cyclic GMP) in mammalian central nervous system (CNS). The longterm objective is to define some of the roles of these cyclic nucleotides in CNS metabolism and function. Major goals are: 1) to determine the anatomical localization of the cyclic AMP and cyclic GMP systems in CNS and to define some of the biochemical and functional processes which regulate cyclic nucleotide metabolism in specific regions of CNS. 2) To explain the relationships of the two cyclic nucleotides to cellular depolarization and seizure discharges and to determine how cyclic AMP and cyclic GMP are involved in the neuropharmacologic actions of anticonvulsant drugs. Newly developed quantitative and qualitative histochemistry methods and techniques will be used to study normal and morphologically and functionally altered brain tissue. It is anticipated that achievement of the above goals will elucidate the roles of cyclic nucleotides in CNS and, in turn, explain some molecular mechanisms underlying normal and abnormal neurological function. In addition, these studies will provide a better understanding of the neurochemistry and neuropharmacology of epilepsy and its therapy.